1. Field of the Invention
Exemplary embodiments of the present invention relate to a display apparatus. More particularly, the present invention relates to a display apparatus capable of displaying a three-dimensional image without glasses.
2. Discussion of the Background
A three-dimensional (3D) image display apparatus typically displays a 3D image using a stereoscopic display technique or an auto-stereoscopic display technique.
The auto-stereoscopic display technique is classified into a glass-type and a non-glass type. A glass-type auto-stereoscopic display changes a polarizing direction of a left-eye image and a right-eye image using a patterned retarder or displays the left-eye image and the right-eye image during different time periods to provide a 3D image to observers.
A non-glass type auto-stereoscopic display includes a parallax barrier panel to separate an axis of the left-eye image from an optical axis of the right-eye image. A display apparatus including a parallax barrier panel provides the left-eye image and the right-eye image to left and right eyes of an observer through slits disposed across the parallax barrier panel.
However, since the positions of the slits are fixed in the parallax barrier panel of the display apparatus, the observer needs to be distant from the display apparatus by a fixed focal length in order to watch a 3D image.